To write yesterday’s piece about Jeb Bush in his own words, I spent almost a dozen hours listening to interviews he’s given over the past few years. I was mostly interested in his comments on his own identity, but every once in a while he said something revealing on other subjects entirely.

Here’s one curiosity, probably not that important in the scheme of things, but still oddly interesting.

In the course of a very friendly interview with Jay Nordlinger of National Review, conducted in June 2011, former Governor Bush argued for favoring domestic energy production as part of a pro-growth economic strategy. (The relevant discussion starts at 47:37.)

“We need a domestic energy policy that would create a huge burst of economic activity. We spend $400 billion a year net going out to places where there’s not any economic activity attached to it—no investment, no jobs created in our country—because we are dependent on foreign oil. And we have more resources, more natural gas and oil resources perhaps, than any country in the world today.”

So far, so familiar. Then immediately follows something weird:

“We’re like Rome at the end of the empire. The Romans went and sought resources from the furthest part of their empire at the highest cost, with huge security implications, rather than try to develop resources closer in. We’re doing the same thing, and it’s just boneheaded.”

Where’d that come from?

Jeb Bush has a keen interest in many policy areas, but who suspected that the economic history of the late Roman Empire was one of them?

What seems to have happened is that somewhere along the way, Jeb Bush encountered a factoid from the Roman writer Pliny. (The elder Pliny, for those keeping score at home.) In around 70 AD, Pliny complained about Rome’s eastern trade in spices, jewelry, and silks. “And by the smallest computation, India, China, and that peninsula [Arabia] take 100 million sestertii from our empire every year—so much do our women and our luxuries cost us.”

Pliny’s lament inspired one of the most famous passages in Edward Gibbon’s Decline and Fall of the Roman Empire. Gibbon—a friend and admirer of Adam Smith’s—derided Pliny as “inquisitive but censorious” and pointed out that the silver actually became more abundant inside the Roman Empire in the 250 years after Pliny worried it was all flowing away. Nonetheless, Gibbon couldn’t resist jumping off from Pliny’s comment to one of his exuberant rhetorical setpieces. It opens: "The most remote countries of the ancient world were ransacked to supply the pomp and delicacy of Rome …” and continues in full at the bottom of this post.

All of us haul such half-remembered fragments of information from decade to decade. From Pliny, to Gibbon, to perhaps a teacher at Andover or a professor at the University of Texas, to the mind of a potential president of the United States: It’s an epic journey.

The trouble is that a half-remembered fragment can inspire an unconsidered thought. As Edward Gibbon’s friend and correspondent Adam Smith taught the world, there’s nothing inherently impoverishing about trading metal for spices or fabrics, any more than there is anything inherently enriching about trading spices or fabrics for metals. Whatever caused the fall of the Roman empire, 400 years after Pliny, it was not the shopping habits of aristocratic Roman women.

It’s worth pointing this out because Jeb Bush cited his fragment of Roman history to support some poorly considered present-day policy. When Jeb Bush summoned up Pliny in 2011, the United States was already half a decade into the greatest surge in oil and gas production since the 1960s. The country was already the world’s number-three oil producer in 2011, on its way to attaining the number one position in 2014. Yet the economic and job situation in 2011 remained very dire, despite this energy boom. Now the oil price is tumbling, energy projects are being canceled and U.S. job growth is nonetheless surging.

It almost seems to suggest that what matters for economic growth is much less the provenance of oil (foreign vs. domestic) and much more its price—just as Adam Smith would have predicted, and counter Pliny, if Pliny had ever heard of oil. As for Jeb Bush, this stray glimpse inside his mind confirms a saying of John Maynard Keynes: “Practical men who believe themselves to be quite exempt from any intellectual influence, are usually the slaves of some defunct economist.”

Here's the passage from Gibbon in full:

The most remote countries of the ancient world were ransacked to supply the pomp and delicacy of Rome. The forests of Scythia afforded some valuable furs. Amber was brought over land from the shores of the Baltic to the Danube; and the barbarians were astonished at the price which they received in exchange for so useless a commodity. There was a considerable demand for Babylonian carpets and other manufactures of the East; but the most important and unpopular branch of foreign trade was carried on with Arabia and India. Every year, about the time of the summer solstice, a fleet of a hundred and twenty vessels sailed from Myoshormos, a port of Egypt, on the Red Sea. By the periodical assistance of the Monsoons, they traversed the ocean in about forty days. The coast of Malabar, or the island of Ceylon, was the usual term of their navigation, and it was in those markets that the merchants from the more remote countries of Asia expected their arrival. The return of the fleet of Egypt was fixed to the months of December or January; and as soon as their rich cargo had been transported on the backs of camels, from the Red Sea to the Nile, and had descended that river as far as Alexandria, it was poured, without delay, into the capital of the empire. The objects of oriental traffic were splendid and trifling; silk, a pound of which was esteemed not inferior in value to a pound of gold; precious stones, among which the pearl claimed the first rank after the diamond; and a variety of aromatics, that were consumed in religious worship and the pomp of funerals. The labour and risk of the voyage was rewarded with almost incredible profit; but the profit was made upon Roman subjects, and a few individuals were enriched at the expense of the Public. As the natives of Arabia and India were contented with the productions and manufactures of their own country, silver, on the side of the Romans, was the principal, if not the only instrument of commerce. It was a complaint worthy of the gravity of the senate, that in the purchase of female ornaments, the wealth of the state was irrevocably given away to foreign and hostile nations. The annual loss is computed, by a writer of an inquisitive but censorious temper, at upwards of eight hundred thousand pounds sterling. Such was the style of discontent, brooding over the dark prospect of approaching poverty. And yet, if we compare the proportion between gold and silver, as it stood in the time of Pliny, and as it was fixed in the reign of Constantine, we shall discover within that period a very considerable increase. There is not the least reason to suppose that gold was become more scarce; it is therefore evident that silver was grown more common; that whatever might be the amount of the Indian and Arabian exports, they were far from exhausting the wealth of the Roman world; and that the produce of the mines abundantly supplied the demands of commerce.

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